Circuit breakers are commonly found in substations and are operable to selectively open and close electrical connections. Typical dead tank circuit breakers have pole assemblies that include first and second electrical conductors in associated bushings. As is known in the art, electrical power lines are coupled to first and second electrical conductors, and the circuit breaker selectively opens or closes the electrical connection there-between. A bell crank or other actuating assembly is associated with a respective pole assembly. The bell cranks are interconnected by a gang-style rotary or push-pull linkage so that all three poles assemblies are actuated at the same time by a single operating mechanism.
As voltage ratings for three pole operated, dead tank circuit breakers become larger, the pole spread gets larger. As a result, conventional rotary or push-pull inter-phase linkage introduce lag into the breaker operation. To prevent lag, the linkage must be made larger, increasing weight and the energy required of the operating mechanism. In push-pull configurations, the rod of the linkage must stand up to compression over a long time span, which can lead to buckling.
Thus, there is a need to provide circuit breaker linkage structure that uses a pull-pull configuration where the inter-phase connection rods are always in tension.